You need to add two things to this graphic: at the html page...

<img border="0" src="http://localhost/cgi-bin/grafem@il.cgi" alt="this
+ is my email" width="144" height="13">
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to call the script. And at the end of the script...

print "Content-type:image/png\n\n";
print $gd->png;
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To fit an image into what was expected (see the content-type).